In this paper a multi-objective optimization model is developed to determine the best size of grid independent solar-diesel-battery based hybrid energy system. The primary objective is to minimize life cycle cost and secondary objective is to minimize CO 2 emissions from the system. These objective functions are subjected to the constraints imposed by the power generated by the system components, reliability of the system and state of charge of the battery bank. The decision variables included in the optimization process are the total area of PV arrays, number of PV modules of 600 W p , number of batteries of 24 V and 150 Ah, diesel generator power and fuel consumption per year. A computer program is build up in C programming language to determine the specifications of hybrid system components. The proposed method has been applied to an un-electrified remote village in Moradabad district of Uttar Pradesh, India. Results shows that the optimal configuration of an autonomous system is PV area of 300 m 2 , 60 PV modules of 600 W p , 160 batteries of 24 V and 150 Ah and a diesel generator power of 5 kW. This system involves PV penetration of 86% and a diesel fraction of 14% having LCC of $110,546 for 25 years, fuel consumption of 1150 l/year and CO 2 emissions of 0.019 tCO 2 /capita/year.